Gas burner



M. THORSON Feb. 12, 1935.

GAS BURNER Filed July 21, 1935 2 Sheets-Sheet 1 Feb. 12, 1935;

Filed July 21; 1953 2 Sheets-Sheet 2 Patented Feb. 12, 1935 7 GAS BURNERMartin Thorson, St. Charles, Ill.

. Application July 21, 1933, Serial No. 681,431

7 Claims.

This invention relates to heating devices, and has to do with a gasburner particularly suitable for use in heating plants and the like.

One of the main objects of my invention is to provide a gas burner ofsimple construction and operation which can be applied with expeditionand facility to heating plants of known type and which is highlyeconomical in the use of gas. A further object is to provide a burner inwhich the parts thereof are effectively cooled by air which is employedto support and promote combustion. Another object is to provide meansfor thoroughly mixing the air with the gas and for heating this mixturepreliminary to combustion thereof so as to promote complete combustionof the resulting mixture, this mixture employing a large volume of airin proportion to the volume of gas. Further objects and advantages of myinvention will appear from the detail description.

In the drawings:-

Figure 1 is a fragmentary vertical sectional view through the lowerportion of a heating plant embodying a burner in accordance with myinvention, parts being shown in elevation;

Figure 2 is a section taken substantially on line 22 of Figure 1, on anenlarged scale;

Figure 3 is a section taken substantially on line 3-3 of Figure 1, on anenlarged scale;

Figurel is a section taken substantially on line 44 of Figure 3; c

Figure 5 is a section taken substantially on line 5-'-5 of Figure 3;

- Figure 6 is a section taken substantially on line 6-6 of Figure 2, onan enlarged scale;

Figure 7 is a section taken substantially on line 77 of Figure 6;

Figure 8 is a section taken substantially on line -8-8 of Figure 7;

Figure 9 is a transverse vertical sectional view through a modified formof burner embodying my invention, and associated parts. I

This application is a continuation in part of my application for Gasburner, filed January 23, 1933, Serial No. 652,995.

In Figure 1 I have illustrated a burner embodying my invention asapplied to a furnace of a domestic hot air heating system of known type,by way of example. The furnace is of known construction and comprises acasing 1 within which is a fire-box provided with a refractory lining 2.Furnaces of this type are commonly provided with 'a grate structurecomprising an outer ring section 3 and a central circular section which,in applying my burner, is removed. An ash pit 4 is provided beneath thegrate and, when my burner is installed; the ash pit door is removed andis replaced by a suitable plate 5 secured in position in any suitable orpreferred manner.

Preferably,

a layer of refractory 6 is placed upon the grate ring 3 and serves toshield the parts within the 5 ash pit from the heat within the fire-box.

The burner 7, which is of circular shape in plan, is suitably supportedwithin the ash pit 4, as by means of an angle iron ring 8 within whichthe burner seats, this ring being supported by suitably disposed legs 9.A plurality of tubes 10 extend from the burner 7 and are inclined upwardand inward thereof at an angle of approximately 45 degrees. these tubesand are provided with suitable open- Tips 11 are secured in the upperends of ings through which the air and gas mixture is discharged, thismixture being suitably ignited so that combustion thereof occurs as themixture leaves the openings of the tips. of suitable refractory materialextends upwardly An air dome 12 upper portion of the dome and flow overopenings 12a provided in the upper portion of the dome. Thedome is thusheated at its upper portion, to a high temperature, the heated airflowing through the openings 12a into the fire-box for supporting andpromoting combustion of the mixture discharged through the tips 11. Inaddition, the flow of the flames and the hot products of combustionacross the openings 12a serves to draw air through these openings, thusinducing air into the dome 12 and through the conduit 14 and base 13,this action supplementing the natural flow of air due to heating of theupper portion of the dome and assuring adequate supply of air throughthe openings 12a. r

The burner comprises an outer air manifold 15 of circular shape in planand of circular crosssection, and an inner gas manifold 17 shapedsimilarly to manifold 15 and disposed in concentric relation thereto.

Manifold 15 is provided 'grees.

Manifold 17 is provided with bosses 19 der suitable pressure. 1

disposed in aligned and concentric relation to the respective bosses 18.Air tubes 10 are screwed into the bosses 18, and gas tubes 20 arescrewed into the bosses 19 and extend upwardly within tubes 10 inconcentric, spaced relation thereto. Each of the gas tubes 20 isprovided, at its upper end, with an outwardly projecting shoulder 21which fits snugly within tube 10. This shoulder is provided with aplurality of air passages 22 extending therethrough and inclined acrossthe axis of the tube 20 at an angle of approximately degrees thereto,the passages 22 being all similarly directed. An orifice plug 23 isscrewed into the outer end of gas tube 20, this plug being provided witha restricted orifice 24 through which duit 15, this pipe extendingthrough plate 5 and receiving air under-pressure from a blower 26 ofknown type which may be driven in any suitable. manner, conveniently byan electric motor.

" A gas pipe 27 is disposed withinpipe 25 in concentric'spaced relationthereto and is connected to gas manifold 17 for supplying gas theretoun- The flow of air and gas to manifold 15 and manifold 17,respectively, is

"controlled by a valve 28 disposedin pipe 25. This valve is shown indetail in Figures 3 to 5, inclusive, and comprises a suitable casing 29within which a plug valve 30 is mounted for rotation, this valve beingprovided at one end with a flange 31 which contacts the adjacent end ofthe and has its inner end disposed adjacent the casing, there being aretaining ring 32 suitably secured on the other end ofthe valve andcontacting the other end of the casing. Valve casing 29 is provided withpairs of air ports 33 open-' ing into air pipe 25, and with a gas port34 disposed between ports 33 at one side of the valve casing, port 34being suitably bored and threaded for reception of the outer end of gaspipe 2'7 which screws into this port. The valve casing 29 is furtherprovided with a flanged nipple 35 extending therefrom and disposedmidway between the air ports 33. Nipple 35 isconnected by a pipe 36 andT 37 to a gas main-38. A- tube 39 extends from the T 37 into thefire-box of the furnace upper endsof the burner tips 11, this tubeproviding a pilot light for igniting the combustible mixture dischargedfrom the burner. A suitable valve40 is interposed in tube 39 forregulating 7 flow of gas therethrough. Valve 30 is provided ..with twoair passages 41 extending diametrically thereof, and is furtherprovided, between the passages 41, with an arcuate gas passage 42. Whenthe valve plug 30 is turned into its full open position, the ends of theair passages 41 are in regprovided with metering openings 44therethrough for determining the maximum flow of air through the valve.The parts are so related that the volume of air has the properproportion to the volume of 'gas to assure maximum efliciency oftheburner from the standpoint of combustion, it

being desirable to employ the maximum volume of air consistent withproper combustion of r the me- .8!??- e ep re en the sa ve-1 he- 9? .gasand the air and prgper; pre-h -.-Pr ie 1a t isqh reep th smixiurathr uehof air and of gas may be regulated as desired,

while maintaining the proper proportion there-,

the air'manifold 15, through pipe 25 and gas is 7 supplied underrelatively low pressure to gas manifold 17 through the gas supply pipe27. The

gas issues through orifice 24 into the space above shoulder 21, and theair enters this space through theinclined passages 22, these passagesserving 7 to impart rotation to the entering air. The space betweentheupper face of shoulder 21 and the upper end, of tip 11 constitutes amixing space,

and the gas and the air are subjected to high rotary turbulence withinthisspace, which. assures thorough inter-mixing of the gas with the air.This mixture is then discharged through thetip openings 11a, and isignited in the manner previously stated. After the burnenhas been -in,op-:-1

eration .for a short time, the flap er portion of the dome 12 becomes'highly heated; and contributes to efficient combustion, sincetheburning mixture is ejected against the upper portion of this dome, asabove described. The heated;

air flowing through the openings 12w contributes further to combustion,with the result that complete combustion of thefuel is assured-andalarge amount of heatis generatedbya comparatively small amount of gaseonsumed. lt will beg noted from Figure 1 that the upper portions of thetubes 10 and tips 11, in which' the mixing space is located, aredisposed adjacent the;dome 12 so as to be exposed .to'the radiantheat ofthe dome and the radiant heat of the refractory lining for the fire boxand the grate ring. This is advantageous, in that the air and gasmixtureis heated preliminary to issuance thereof through the openings 1141,this preliminary heating concold. It will also be noted that the airflows around the gas supply tube 27 andthe gas manifold 17, as well asaround the gas tube-20,. and is effective for cooling the same. ;'I'his;is .advantageous as avoiding objectionable heating of any parts ofthe burner and associated elements disposed below the grate ring of thefurnace.

I find thatthe proportions between'the various conduitsand passages ofthe burner,al fect.

the efiiciency of operation thereof. For ,most

efiicient operation, assuming-that the air mani fold has an interiordiameter of two inches, the gas manifold should havean interior cliameter o l in h the nt r o diamet ttube 10 should be three-eighthsof aninch,;the interior dia meter of thegas tube20should be threesixteenthsof an inch, and the interior diameter of tip 11 should be three-eighthsofaninch. The

have a diameter of one .-sixty fgurth of an; inch. It is also desirablethat the length ofthe mixing space abovethe shoulder 21,- andextendingto'the upper end of the tip 11, be approximatelyonethird of thetotal length ofthe-tip l1-,a nd tube 10. This assures thoroughintermixing of the ea n ere tributing to combustion andavoiding thermahflosses such as would occur if the mixture-were.

the tip openings 1111, as above set forth. Though the proportionsbetween the various passages and openings may be varied somewhat,I'findthat the proportions above stated give the most satisfactory resultsfrom the standpoint ofefficiency and economy in operation.

In Figure 9 of the drawings I have illustrated a modified form of burnersuitable for use in connection with hot water or steam heating systems.This burner is similar in construction and operation to the burnerillustrated in Figures 1 to 8, inclusive, with the exception that airtubes 10a and tips 11 are inclined upward and outward at an angle ofapproximately 45 degrees, instead of being inclined upward and inward,so that the flame is directed outward and toward the surrounding waterwall of the fire-box of a furnace in which the burner is disposed.Otherwise, the construction and operation of the burner is the same asthat above described, and need not be set forth in detail.

What I claim is:-

1. In a gas burner, an outer manifold, an inner manifold within saidouter manifold, means for supplying air under pressure to said outermanifold, means for supplying gas under pressure to said inner manifold,a series of burner assemblies extending upward from said manifolds, eachof said assemblies comprising an outer air tube secured to andcommunicating with said outer manifold, an inner gas tube within andspaced from the air tube and secured to and communicating with saidinner manifold, an annular member interposed between said tubes adjacentthe upper end of said inner gas tube and provided with passages inclinedwith respect to the axis of said gas tube, and a relatively longcylindrical tube extending beyond said annular member and defining arelatively long mixing chamber extending beyond said passages, saidpassages discharging air from said outer air tube into said mixingchamber with a whirling motion, said inner gas tube discharging gas intosaid mixing chamber within the whirling volume of air, said cylindricaltube being provided at its outer end with a restricted orifice.

2. In a gas burner, an outer air tube, an inner gas tube within andspaced from the air tube, an annular member disposed between said tubesadjacent the upper end of said inner gas tube and provided with passagesinclined with respect to the axis of said gas tube, a relatively longcylindrical tube extending from the upper end of said air tube anddefining a relatively long mixing chamber extending beyond saidpassages, said passages discharging air from said air tube into saidmixing chamber with a whirling motion, said inner gas tube discharginggas into said mixing chamber within the whirling volume of air, saidcylindrical tube being provided at its upper end with a restrictedorifice, and means for supplying air and gas to the respective tubes.

3. In a gas burner, an outer air tube, a gas tube extending upwardlywithin the air tube in spaced relation thereto and provided at its upperend with a restricted gas outlet orifice, said gas tube having an outershoulder adjacent its upper end fitting snugly within the air tube andprovided with passages inclined with respect to the axis of said gastube, a relatively long tubular tip member extending from the upper endof the air tube and provided at its upper end with a restricted fuelmixture outlet orifice, said tip member being of substantially uniforminterior diameter and defining a relatively long mixing chamberextending u warmy beyond saidshoulder and the gas outlet orifice-vofs'aid gastube, the interior diameter of said mixing chamber 7 beingmaterially greater than the diameter of thegas tube, and means forsupplying aira'nd; "gas under pressure to the respective tubes.

4. In a gas burner, an outer air tube, a gas tube extending upwardlywithin the air tube in spaced relation thereto and provided at its upperend with a restricted gas outlet orifice, said gas tube having an outershoulder adjacent its upper end fitting snugly within the air tube andprovided with passages inclined with respect to the axis of said gastube, a relatively long tubular tip member extending from the upper endof the air tube and provided at its upper end with a restricted fuelmixture outlet orifice, said tip member being of substantially uniforminterior diameter and defining a relatively long mixing chamberextending upwardly beyond said shoulder and the gas outlet-orifice ofsaid gas tube, the interior diameter of said mixing chamber beingmaterially greater than the diameter of the gas tube, said tip memberbeing exposed for the major portion of its length to the heat incidentto combustion of the fuel mixture issuing from the upper end of the tipmember, and means for supplying air and gas under pressure to therespective tubes.

5. In a gas burner, an outer cylindrical air tube, a cylindrical gastube extending upwardly within the air tube in concentric spacedrelation thereto and provided at its upper end with a coaxial restrictedgas outlet orifice unobstructed for discharge therethrough of gas in asolid stream, said gas tube having an outer shoulder adjacent its upperend provided with passages inclined with respect to the axis of the gastube, a relatively long tubular cylindrical tip member extending fromthe upper end of the air tube concentrically therewith and provided atits upper end with a restricted fuel mixture outlet orifice, said tipmember being of a substantially uniform interior diameter materiallygreater than the diameter of the gas tube and defining a relatively longmixing chamberextending upwardly beyond said shoulder and the gas outletorifice of said gas tube, and means for supplying air and gas underpressure to the respective tubes.

6. In a gas burner, an air manifold, a gas manifold within the airmanifold in concentric spaced relation thereto, burner tube assembliesextending from the manifolds at an inclination upward and inward andeach comprising an air tube communicating at its lower end with the airmanifold and a gas tube within the air tube and communicating at itslower end with the gas manifold, tip members extending from the upperends of the air tubes and defining mixing chambers extending aconsiderable distance above the upper ends of the gas tubes, and ahollow refractory member disposed between said tip members and extendingthereabove, said assemblies being disposed to direct the burning air andgas mixture against the upper portion of said refractory member, therefractory members being open at its lower end for admission of airthereto and having openings adjacent its upper end for supplying heatedsecondary air to the zone of combustion.

7. In a gas burner, an air manifold, a gas manifold within the airmanifold in concentric spaced relation thereto, burner tube assembliesextending from the manifolds at an inclination upward and inward andeach comprising an air tube communicating at its lower end with the airmanifold

